Masaki Hashimoto of the eight-member group timelesz has been cast as the lead in “Onee-chan no Midori-kun” (お姉ちゃんの翠くん), which is set to be released in theaters on December 4. Based on the popular manga of the same name by Amu Meguro (also known as “My Sister’s Midori-kun”), the movie tells the bittersweet love story of Sui Sanae, a high school girl who falls in love with Midori Yukishiro, her older sister’s boyfriend.
Masaki, who is making his film debut, takes on the role of Midori, the “beloved older heartthrob” who captivates everyone with his mature composure, occasional childlike expressions, and overwhelming kindness. Meanwhile, actress Runa Nakashima—winner of the Japan Academy Award for Best Newcomer—plays Sui, a tsundere-type student struggling with her feelings for Midori. She portrays the sincere yet painful emotions of falling in love with someone she “must not love.”
The picture is directed by Mahito Kimura, known for his delicate portrayals of romance in dramas such as “Ao Haru Ride” (2023–2024) and “Strobe Edge” (2025–2026). The screenplay is written by Nami Yoshikawa, who has worked on numerous romance films, including “Honey Lemon Soda” (2021) and “Our Secret Diary” (2023). Together, they will carefully depict the sparkling beauty of pure unrequited love—and the ultimate heartbreak of not being able to confess those feelings.
The story also follows the characters from high school into university and adulthood, portraying the frustrations and misunderstandings that arise as circumstances change over time. The film aims to capture realistic emotions of love that audiences of all generations can relate to.
The newly released teaser visual features the film’s symbolic fresh green color and a clear blue sky, with sparkling lights reminiscent of a snow globe. In the image, Midori gently lifts Sui‘s chin with a pen while smiling slightly, while Sui gazes at him in surprise. Their subtle distance from one another conveys Midori‘s presence as the “older boy she admires” and the sadness of a love that can never truly be reciprocated.
Comments from the cast and creators
Masaki Hashimoto
“I am Masaki Hashimoto of timelesz, and I will be playing Midori-kun in the film Onee-chan no Midori-kun.
I was honestly shocked when I learned I would be starring in the film.
After reading the original manga, I became deeply fascinated by Midori myself.
He may seem teasing or mischievous, but he’s actually kind and mature. At the same time, there are moments when you can see the conflicts hidden behind that kindness. I think that contrast is part of what makes him so charming.
Not only Midori, but the entire story and all of its characters are wonderful.
I want to approach both Midori and this work, which fans cherish so much, with complete sincerity and dedication.
Director Kimura, Nakashima-san, and I have already discussed how we want to carefully portray every subtle emotional change, glance, gesture, and expression.
I hope the result will be a delicate story that tugs at the heart.
Nakashima-san is a wonderful person, just like Sui—straightforward and compassionate.
Her acting is incredible, and there are moments when I find myself learning from her.
Filming is still ahead of us, but I hope everyone involved can come together to create the best possible film.
The movie opens nationwide on December 4!
We hope to see you in theaters this winter.”
Runa Nakashima
“I was truly thrilled when I learned I would be appearing in ‘Onee-chan no Midori-kun.’ It was already a manga I loved and had read before.
I’m also very excited to step into the world created by Amu Meguro-sensei.
I want to carefully portray Sui-chan, preserving the cute and delicate atmosphere of the story while showing both her prickly side and her underlying charm.
Masaki Hashimoto perfectly matches Midori’s gentle and kind aura, and every rehearsal makes me feel more strongly that he is becoming the character.
Watching him motivates me to work even harder as I prepare for filming.
I hope everyone looks forward to the movie’s release.”
Original Author Amu Meguro
“I never imagined this work would receive a live-action adaptation, so I’m still both nervous and incredibly happy.
Hashimoto-san looks as though he stepped straight out of a shojo manga. His face, proportions, and overall sparkle are simply amazing!
It’s not just his appearance; the softness of his presence and the atmosphere he carries perfectly match the image of Midori I had in mind.
Nakashima-san has such incredible transparency and cuteness that she almost seems translucent.
When I saw her make Sui’s characteristic grumpy expression, I instinctively exclaimed, “So cute! That’s Sui!”
It’s a great honor to have these two portray Sui and Midori, and I’m also fortunate to be working with such an excellent production team.
I’m already very excited about the project.”
Director Mahito Kimura
“Jade gemstones contain beautiful impurities of many different colors.
Likewise, this story is filled with contradictions and conflicts—feelings people try to suppress because they believe they shouldn’t be honest about them. These emotions are like impurities that cannot be controlled.
That is why I feel this is a wounded yet beautiful story about people who are trapped by such feelings and cannot be proud of falling in love, but who gradually become aware of themselves and grow.
Hashimoto-san’s soft and gentle presence reminds me of the unique aura that surrounds Midori. I have high hopes for how naturally he will embody the character.
Nakashima-san possesses both fragility and an inner strength that reflects someone truly living in the present. The magnetism of her eyes is exactly like Sui.
I look forward to seeing her portray a young woman who struggles but always keeps moving forward.
As the characters accumulate the regrets of youth, gain their own wings, and graduate from their past, I believe they will shine with a beauty like jade itself.
With the utmost respect for Meguro-sensei’s original work, the cast and staff will carefully embrace Onee-chan no Midori-kun and create a love story that resonates deeply with people’s hearts.”
More timelesz on Social Media
Watch “timelesz project -AUDITION-“
More timelesz on Dumpling Box
![[S DRAMA] “MEMORY ACQUIRER” Ep.1 The Night That Vanished—Now Streaming with English Subtitles on YouTube](https://dumplingbox.org/wp-content/uploads/2026/04/S-DRAMA-ENG-SUBS-1280x720.png)
Something went wrong. Please refresh the page and/or try again.